Second generation (2G) cellular telecom networks have been in commercial use since 1991, and include GSM (Global System for Mobile Communications) for voice, with which Enhanced Data rates for GSM Evolution (EDGE), Enhanced GPRS (EGPRS), may be used. EDGE/EGPRS is a backward-compatible digital mobile phone technology that allows improved data transmission rates, as an extension on top of standard GSM on 2G networks. Although 2G networks allow for both digitally encrypted voice conversations and data services, they do not permit simultaneous voice and data communications. Thus, all data traffic to 2G mobile electronic devices is blocked whenever a user is engaged in a voice call. If the user is on a call for an extended period of time, there may be circumstances in which critical data is prevented from reaching the device. For example, a user may be on an extended call while supervisors or family members are urgently trying to contact him/her via email. Or, if a user's mobile device has been lost or stolen and an authorized voice call is made from the device, any attempts to remotely disable the device (e.g. an IT kill command) will fail while the voice call is in progress. The same shortcomings apply to CDMA (Code Division Multiple Access) cellular telecom networks.
Third generation (3G) cellular telecom networks, including UMTS, permit simultaneous voice and data traffic but require a much longer time (second(s)) to establish a call, which introduces latency in the receipt of data. Also, since the radio must be on for several seconds before any data is exchanged, 3G devices exhibit heavier battery use. In addition, UMTS connections use more power while in an idle state than 2G devices. For at least these reasons, 2G devices continue to remain popular.
Accordingly, it is desirable to provide integration of voice and data services over networks that do not support simultaneous voice/data communication, such as CDMA and 2G cellular telecom networks. It is also desirable to provide a mechanism for faster downloading of important data to 3G devices that are in use for voice calling.